A power milling machine typically has a drive shaft rotatably mounted in a housing, a rear end thereof projecting out from the housing and having means for coupling to a rotary drive and a front end thereof projecting out from the housing and carrying a milling tool, in particular a milling disk that is mounted with an axial hole onto a washer stack retained on the front shaft end by annular clamping elements, and abuts against an abutment fixed to the shaft, it being possible to clamp a washer stack thereof in a friction-locked manner by a clamping assembly against the inner surface the hole of the tool.
With such a device, for example, a toothed belt wheel coupled to a rotary drive is fixed at the rear end of the drive shaft rotatably mounted in the housing. The device may be arranged with the housing as a part of a machine or apparatus.
A milling tool, example, a milling disk, is fixed at the front end of the drive shaft projecting out of the housing. The milling tool has a central hole by means of which it can be mounted onto a washer stack that has annular clamping elements on the shaft end. The shaft also carries an abutment against which the milling tool can be pressed. To fix the tool, the washer stack with the annular clamping elements can be clamped by a clamping assembly which is formed, for example, by a clamping head and a clamping screw. The clamping head is supported on the end of the tool and/or the washer stack. The screw is fixed and braced against the end of the drive shaft. If the tool is worn out or must be switched for any other reason, then it is necessary to loosen and remove the clamping assembly in order to be able to remove the tool from the washer stack with the annular clamping elements and replace the tool with another tool. This approach is costly and requires another tool, typically a pair of wrenches, and the space available often makes handling and fitting of the fresh milling tool difficult, because the space is covered with other parts of the device or the corresponding machine.
The washer stack with the annular clamping elements is a known clamping element that can apply an axial force through the clamping assembly to expand the washer stack radially with the annular clamping elements and brace it against the inner surface of the hole of the tool. Thus, torque is transmitted to the tool that is locked on the drive shaft.